Rubber article.



s. 1. & LA. rmnms.

aua'asn ARTICLE.

APPLICATION FRED OCT 3h 9H:

1,266,936. V Patented May 21, 1918.

- \/5 TD x UNITED STATES PATENT OFFICE.

Bunsen ARTICLE.

specification of Letters Patent.

Patented May 21, 1918.

Application filed October 31, 1917. Serial 1T0. 198,405.

To all whom it may concern:

Be it known that we, SAMUEL J. Haunts sand ALLAN A. HARRIS, citizens of the United States, residing at Randolph, in the county of Norfolk and State of Massachusetts, have invented a new and useful Improvement n Rubber Articles, of which the following is a specification.

This invention relatesto rubber articles having surfaces that are subjected to seyere wear, such for instance, as heels, soles, t res, crutch tips and the like, and it is part cularly concerned with articles of this kind which are provided with friction plugs or inserts designed to prevent slipping or to increase the wear resisting qua ities of the articles. These pin or inserts usually are secured in the-hee, sole or other article merely by the adhesiveness of the rubber,

and in order to promote this adhesion it is usual to impregnate the parts of the plug with rubber cement prior to the vulcanizing operation. It is found, however, that the bond or union thus formed between the plug and the rubber body of the article is often destroyed after the article has been in service for only relatively a short "time, or when it is subjected to a hard usage, andthe plu consequently are allowed to drop out of t e article.

The present invention is directedto 'the solution of the problem presented by these conditions, and it aims to devise a thoroughly practical means for securing plu of this character in rubber articles and improve the methods of manufacture of rubber. articles provided with inserts of this character. I

The invention will be readily understood from the following description of the invention as embodied in a rubber heel and the novel features will be ointed out more in the a pen ed claims. Referrin nowto t e drawin Figure is a lan' view 0 face of a rubber eel having several. friction plugs embedded in it;

Fig. 2 is a transverse, cross sectional view through the molds in which the heel is formed and shows the construction of the. pllllgs in the heel. shown in Fig. 1;

.' 3 is a cross sectional view on a large scale of a friction plug .of the construction shown in Fig. and shows the plug pro vided with a cap and jacket;

them in the body of the heel.

the tread what difi'erent form of plug; and

Fig. 6 is a cross sectional view of another form of plug.

Fig. 1 of the rawings shows a heel 2 provided with three friction plugs 4 which are embedded therein and have their ends exposed at the tread face of the heel.

The plu may be made out of any suitable material but according to the preferred method they'are made of some textile fabric, such for instance, as canvas or duck impregnated or coated in the usual way with rubber cement and rolled on an arbor of an appropriate size. The roll of fabric so formed is then cut up to form plugs of the desired length. These plugs referably are then pressed in suitable ice or presses to corrugate their eripheral surfaces or shape their perip cries in some manner that will serve to mechanically look In the construction shown in Fig. 3 the peripheral surface of the plug 4 has been corrugated as just described; A rubber jacket 6 is then rolled around the plugand is corruated, as shown in Fig. 4, by using suitable ies or in any other convenient manner. If desiredthe plug may be partly vulcanized at this stage in the process of manufacture in order to give it more stability. Usually, however, this is'not necessary. In assembling a of each pin 8, and

stock is placed in the molds in the usual way and the vulcanizing operations are performed in the usual manner. Obviously, if desired, the washer ,12 and cap 14 couldbe assembled on the plug prior to placing the plug on the mold pin 12 is then placed at the end of which consists of a disk In following this process it is referable to make the jacket 6 of a somew at better a composition than that which is ordinarily used for heels and to use such a com 081- tion that it will units or bond to the ody of the heel and also to'the plug more, se-

curely than the plug and the body of the 1 hccl would bond to each other if the jacket were not )resent. In other words, the plug is bonde to the jacket and the jacket is bonded to the body of the heel. The composition of the jacket, of course, will depend upon the materialused in making the plug and upon the composition used in the body of the heel; but the proper compound to be used in a iven case will be obvious to those skilled in this art. This feature is regarded as very important regardless of the construction given to the jacket and the plug for the purposeof mechanically locking the plug in the heel. It is obvious, however, that the corrugating of the plug and the pressin of the jacket into the corrugaitions facilitates, through mechanical action, the locking of the p ug in the heel. This corrugated construction ofthe plug and jacket also gives additional surface for the adhesion thereto of the adjacent bodies.

In the construction shown provision is made for driving nails or fastenings throu h the aperture in the pin and through t e hole in the washer 12, which alines with said aperture, these fastenings cotiperatin with those driven through other parts of t e heel to secure the heel to the shoe. The fabric cap 14 distributes the pressure which the nail head applies through the washer 12 to the adjacent parts of the heel, and its union with the 'acket 6 also serves to secure the plug to t e nail and thus enable the nail to exert a substantial amount of holding power on the plug independently of the adhesion of the plug to t e body of the heel. This cap 12 also performs the additional function of preventin therubber stock as it is forced into the mol during the process of manufacture from separating the plies of fabric. It will be noted that the plies of fabric that makeup the plug 4 extend transversely to the tread face of the heel, while the cap 14 at the inner end of this plu extends substantially parallel to the tree face of the heel. Consequently, while the rubber stock is bein forced into the mold againfi the end of t e plug, the cap protects the inner end of the plug from the action of the stock that would tend to tear it apart and force it into a shapeless mass.

The plug shown in Fig. 5 is made by roll ing fabric in the manner above described and then pressing it into the tapered form shown. This plug preferably is also provided with a jacket 6. When inserted in the heel, the small end of the plug is placed at the tread face of the heel; err-that its taperedshape will assist in mechanically looking it in the heel independently of its union withthe adjacent parts of the heel. It is obviomea that if it were desired td'nse a solid plug the" fabric would npt be rolled on an arbor but the manufact urmg processes otherwise would be the same.

as above described is first incased in the jacket 6 without being corrugated and receivcs its corrugated form from the pressure transmitted through the jacket during the corrugation of the latter member.

While we have herein shown and described the best embodiments of the invention of which we are at present aware, it is obvious that these embodiments may be modified in many ways while still retaining the essential spirit and characteristics of the invention.

What we claim as new, is

1. A rubber article having a wear-receiving face, a friction plug embedded in said article and having a portion thereof exposed at said face, and a-rubber jacket of substantial thickness for said plu bonded both to said plug and also to t e body of said article.

2. A rubber article having a wear-receiving face, a friction plug embedded in said article and having a portion thereof exposed at said face, a rubber jacket of substantial thickness encircling said plug and mechanically and adhesively locked both to said plug and also to the body of said article.

3. A rubber article having a wear-receiving face, a friction plug embedded in said article, and having a portion thereof e osed at said face, said plug com rising a p and ity of "plies of fabric exten ing transversely of said face, and a disk of-fabric covering the inner end of said plug.

4. A rubber article having a wear-receiving face, a friction plug embedded in said article and having a portion thereof exposed at said face, said plu consisting of a roll of fabric having the p ies thereof running transversely of said face and a disk of fabric at the inner end of sai plug extending substantially parallel to said face.

5. A rubber article having a wear-receiving face, a friction plug embedded in said article and hafifl' a portion thereof exposed aid f t plug eonsistingof a hollow roll of fabric, a washer at the inner end of said plug having an aperture formed therethrough in alinement with the aperture insaid ping, and a disk of fabric covering said was er.

6.-A frictiortu'iinsert for a rubber article having a wear-receiving face, comprising a plug of material having: its outer surface corru ted, and a rubber jacket of substantial t Y ess adhesively secured to tefi surface and fitting into the nsert for a rubber article having a we'd wiving face, ctimprising a roll of fabric having the layers of said roll extending substantially parallel to the axis of the roll and the outer surface of said roll ha ing corrugations formed therein extend- Lne' vi renm l'erent ially thereof.

Thu improvement in the process of nmnu the! u ring rubber articles provided with friction inserts, which consists in interposing a rubber jacket of substantial thickness between said insert and the body of the artiele of such a composition that it will bond IIUlll to the article and to the insert more seeurelv lhnn the insert and article would lmiul lo each other.

J, that improvement in the process of nmnufueturingrubber articles provided with friction inserts, which consists in providing :in insert. inensing said insert in a rubber jacket n; substantial thickness, operating on said insert and jacket to lock them together, and vuleanizing said insert and jacket in the ljmly of the article.

10. That improvement in the process of manufacturing rubber articles provided with l'rietion inserts, which consists in utilizing a rubber jacket of substantial thickness to incase said insert and secure the insert and article together.

In testimony whereof we have signed our names to this specification.

SAMUEL J. HARRIS. ALLAN A. HARRIS. Witnesses EDITH L. FRENCH, HUBERT F. FRENCH. 

